use std::collections::HashSet;
use std::convert::TryFrom;

use rusqlite::params;

use crate::database::Db;
use crate::id::Id;
use crate::result::RudeResult;
use crate::try_log;
use crate::world::Zone;

impl Db {
	/// Get root zone
	pub fn root_zone(&self, zone: &Zone) -> RudeResult<Zone> {
		// get rid of the &
		let mut zone = Zone {
			id: zone.id,
			parent: zone.parent,
			name: zone.name.clone(),
			users_visible: zone.users_visible,
			areas: zone.areas.clone(),
		};

		// loop until find the root
		loop {
			zone = match self.load_zone(zone.id) {
				Ok(Some(z)) => z,
				Ok(None) => {
					log::error!(
						"{}({}) :: Can't find parent zone :: None value",
						file!(),
						line!()
					);
					return Err(Box::from("None value"));
				}
				Err(e) => return Err(e),
			};

			if zone.id == zone.parent {
				return Ok(zone);
			}
		}
	}

	/// Save a zone to the database.
	pub fn save_zone(&self, zone: &Zone) -> RudeResult<()> {
		let mut statement = try_log!(
			self.0.prepare(
				"insert into zones (id, parent, name, users_visible) values (?, ?, ?, ?) on conflict(id) do update set id=?, parent=?, name=?, users_visible=?;"
			),
			"Unable to prepare sql statement"
		);

		let _ = try_log!(
			statement.execute(params![
				zone.id,
				zone.parent,
				zone.name,
				zone.users_visible,
				zone.id,
				zone.parent,
				zone.name,
				zone.users_visible,
			]),
			"Unable to perform query"
		);

		Ok(())
	}

	/// Load a zone from the database.
	pub fn load_zone(&self, id: Id) -> RudeResult<Option<Zone>> {
		let mut statement = try_log!(
			self.0
				.prepare("select id, parent, name, users_visible from zones where id = ?"),
			"Unable to prepare sql statement"
		);

		let mut rows = try_log!(statement.query(params![id]), "Unable to perform query");

		let mut zone = if let Some(row) = try_log!(rows.next(), "Unable to retrieve row") {
			try_log!(Zone::try_from(row), "Unable to get Zone from Row")
		} else {
			return Ok(None);
		};

		zone.areas = {
			let mut a = HashSet::new();

			let mut statement = try_log!(
				self.0.prepare("select id from zones where parent = ?;"),
				"Unable to prepare sql statement"
			);

			let mut rows = try_log!(statement.query(params![id]), "Unable to perform query");

			while let Some(row) = try_log!(rows.next(), "Unable to retrieve row") {
				let new_id = try_log!(row.get(0), "Unable to retrieve field");
				if new_id != id {
					a.insert(new_id);
				}
			}

			let mut statement = try_log!(
				self.0.prepare("select id from rooms where zone = ?;"),
				"Unable to prepare sql statement"
			);

			let mut rows = try_log!(statement.query(params![id]), "Unable to perform query");

			while let Some(row) = try_log!(rows.next(), "Unable to retrieve row") {
				a.insert(try_log!(row.get(0), "Unable to retrieve field"));
			}

			a
		};

		Ok(Some(zone))
	}
}